What is this CAR T-Cell Therapy Anyway? (CAR T 101)

You may have heard or read a lot about this thing called 'CAR T-cell therapy' - but what exactly is it? Just another cancer fad, a new variation on the same old treatments? Or something new?

The traditional treatments

For many years, the only weapons in the oncologist/hematologist toolkit to fight cancer were variations on the three things patients call 'Cut, Burn and Poison'. Surgery ('Cut') was the first to be used, with the aim of removing a tumor and removing cancer that way; 'Burn' was next - using radiation to kill the cancer cells, after radioactivity was discovered in the late 1800s; and 'Poison', when chemotherapy was developed as a by-product of World War II, after chemists realized some of the deadly concoctions they were developing as weapons could be used to kill fast-growing cells, like cancer.

Yes, new treatments have been regularly developed over the year, but really they have mostly been a refinement of these three basic tools. Tools that hopefully we will look back on in the same way we look back on leeches as a medical therapy now - archaic and primitive, but the best we had at the time.

Until now...

A whole new approach

The human body has evolved over million so years to be a pretty effective organism and in particular, the immune system is an incredibly complex and sophisticated system which is constantly fighting infection - mostly with great effect. Cancer, however, isn't a traditional 'external' infection, it's our own cells.

Sometimes when our cells divide they do so in such a way that the immune system doesn't realize that something has gone wrong, nor does it see the cell as foreign. Cancer IS us, just a slightly weird version of us that multiplies quickly and unchecked.

So the basic idea of CAR T-cell therapy is this - could we somehow give the immune system a helping hand? Could we teach it that the rapidly dividing cells over there, crowding out the normal cells, are not normal - and then let the immune system do its thing?

That's the basic idea behind CAR T-cell therapy. It's a new kind of treatment - part of a new family of treatments called 'immunotherapy' - harnessing the power of the immune system to fight cancer, rather than cut, burn or poison. It's new - meaning we are still working through how best to use it, and what sort of cancers it's effective for. So far, it's proving very effective for blood cancers (and is being trialed for other cancers). It's also not proven well enough that its the first tool the doctors will turn to, but with the amazing results it's showing, perhaps one day it will be.

Elegant and simple, yet unbelievably complex

On one hand, the concept of CAR T-cell therapy could not be simpler - we are using the body's own immune system. But on the other hand, it's also like science fiction - we are editing the genetic makeup of the patient to teach the immune cells to recognize cancer - literally changing their DNA. This stuff would have been science fiction just a few years ago, but now there are many people - including myself - who can walk around as 'genetically modified organisms', and have beaten cancer thanks to this simple - yet complex - treatment.

In a future article, I'll go into more depth as to how the process works and what it's like from a patient's perspective, but for now, I am pleased to report that the oncologist's toolkit has expanded with one new amazing tool in the fight against cancer - and it's ourselves.